Open type searchlight



Oct. 3, 1933.

(Jewe /tor.

, Fresfm/Zbasse ff.

iimt flier/mag Patented Oct. 3, 1933 UNITED STATES PATENT OFFICE OPEN TYPE SEABCHLIGHT Preston 3. Banett, Brooklyn, N. Y., asaignor, by

meme assignments, to Sperry Gyroscope Company, Inc., a corporation of New York Original application June 14, 1918, Serial No.

239,927. Divided and this application September 12, 1923. Serial No. 662.175

8 Claims. (Cl. 1'I651) This invention relates to high intensity flaming holder is insulated by fireproof insulation 8 from arc lights, having special reference to searchthe standard; the current being introduced to lights, and is a d vision of my copending applithe holder by a wire 9. The negative holder is cation, now matured into Patent 1,711,983 dated also shown as bolted to the positive holder at 10 6 May 7, 1929, this patent pertaining more parand insulated therefrom; the current to the negao ticularly to the open type Searchlight. tive holder being introduced by wire 11. A bar 12 One of the objects of this invention is to prowhich leads the current to the negative holder vide means for producing a resultant force upon is shown as supporting it from the positive holder the arc so that said arc may be positioned as and passing over the top of the holders. Prefdesired and maintained in such position. More erably both electrodes are rotated and fed within 5 particularly, the means for producing a resultant their respective holders by any suitable mechaforce upon the arc is herein utilized for directing nism which forms no part of this invention. For the arc toward a ventilating duct, and for renderrotating and feeding the positive electrode, an ing it unresponsive to air currents, or other oscillatory intermittent gripping mechanism 13 15 disturbing forces, thus permitting operation of is illustrated. Said mechanism is operated from 70 the are light in an open-type drum. the shaft (not shown) within the control box,

Another object of this invention is to simplify through a suitable crank shaft (not shown) and and to improve the construction such lamps, link 16. The rate of feed is controlled by adwhereby said operation is obtained, irrespective justing the angle of the member 17 which conof the position of the light, or in other words, trols the advance of the gripping means during 75 whether it s right side up, up side down, or on its oscillation. As said mechanism forms no part end of this invention, and is completely described in A further object is the provision of means for the patent to Theodore Hall, No. 1,625,315 dated supporting the arc lamp mechanism from the April 19, 1927, for flaming arc floodlights, no

lamp shell in themost efficient manner. further details need be given. go

A further object is to secure proper burning .Spring pressed brushes 18 and 19 may also be conditions with a minimum number of parts and provided, said brushes being pressed against the to simplify the ventilation of such lamps. For electrode by spring 20 connected thereto through the latter purpose, I contemplate utilizing one linkage 21. Near the forward end of the holder of the supporting means, hereinbefore mentioned, comparatively large cooling ribs 22 are shown.

as a ventilating duct. The said shields or ribs are shown as secured to- Oth obj cts nd advantages of y invention gether by bolts 24. To said ribs is secured a formore or less broad than hereinbefore stated wardly extending refractory sleeve 23 adapted to w l b in P Obvious and P p fi ally shield the positive electrode up to a point a pre- 35 referred to in the specification. determined distance back of the electrode tip.

In the accompanying drawing in which I have In order to cut off the rays of light from the are shown what I now co ide o b the Preferred which do not strike the reflector, I provide a hood form of my invention, or shield enclosing the arcing tip of the positive- 1 is a Vertical Section u h a searc electrodes on all sides except the side facing the 40 light embodying my invention. reflector. As shown the hood is formed oi a Fig. 2 is an enlarged detail of the lamp sheet metal housing 25 which may or may not be mechanism. formed as a part of said ribs and is shown as Fig. 3 is a sectional view showing the manner secured to the upper end of the ventilating tube 3, in which the current is 'led to the arc. the housing together with the aforesaid end of 45 Fig. 4 is a side view of the electrode holders the tube 3 forming a complete hood or enclosure showing the manner of leading current to the for the arc except the side facing the reflector. arc. Said housing and preferably also substantially Referring to the drawing I have shown the all parts of the holders are formed of non-maglamp mounted on a control box 1. Extending netic material. The housing is shown as secured 50 from said box is a standard 3 of hollow constructo the standard 3 and may be provided with an tion and preferably of elliptical or elongated Opening 26 at the back. Preferably the opening cross-section. To such standard is secured the 45 in the top of the standard extends some disholder 4 and the positive electrode 5. Said stand tance behind the shield 25 as shown in Fig. 3 so ard also preferably supports the holder 6 for that air is also drawn down over the cooling ribs 5 the negative electrode 7. As shown the positive 22. The negative holder is also shown as pro- 10 vided with spring pressed brushes 18', held in place by spring 20'.

The feeding mechanism is shown as comprising feed rollers 28 which are actuated. by the shaft 29 leading to the control box. The mechanism for turning the shaft 29 is enclosed within the control box 1 and may be of any standard type of mechanism for feeding an electrode by voltage control or otherwise.

An electric motor 32 is shown for actuating the feeding and rotating means. The motor shaft passes through a centrifugal blower or other air exhausting means 36, the said shaft serving to operate said blower.

It should be noted that the current passing through the bar 12 travels in the opposite direction from the current passing through the arc. Since very heavy currents are employed in this type of light, preferably 150 amperes or more, I have found that by this simple means, a marked deflecting effect may be produced upon the arc flames. It should be further noted that the electrodes are positioned at an angle, the apex of which is directed away'from the current-carrying member 12. An arc of this character in which electrodes are positioned at an angle, operates substantially as outlined in the patent to Elmer A. Sperry, No. 1,227,210, May 22nd, 1917, according to which a brushing contact by the negative flame across the mouth of the positive crater is effected. I prefer howevercombining the above feature with said method of operating as outlined therein whereby the operation of the arc is assured in all positions of the searchlight. The operation of the form of invention described is as follows:

The exhaust blower 36 creates a continuous downward trend of air through the standard 3, thereby continuously withdrawing the air and fumes from within the shield 25. As the electrodes are positioned at an angle, the arc flames naturally curve toward said opening as outlined in the said patent to Elmer A. Sperry. Since the standard orchimney 3 extends close to the tip of the flame so produced, the downward trend of air carries off immediately the fumes through the standard, while side deflecting currents of air are prevented by the shield. Opening 26 in the back of the shield assures a parallel movement of air from the top of the shield toward the bottom, so as not to deflect the arc flames. In addition, the repelling influence of the oppositely travelling current through bar .12 aids in steadying the arc and in directing it toward the said outlet, irrespective of the position of the searchlight and in assuring the proper brushing contact under all conditions.

In addition to the current through bar 12, additional contactors are placed near the arc to cause other deflections, so that the position of the arc will be the resultant of said deflecting forces.

While the arrangement of conductors is hereinafter described in connection with Fig. 4 wherein the negative holder 6 is placed substantially parallel to the positive holder 4, but is slightly out of line with the same, the negative holder being slightly nearer the repelling conductors than the positive holder, it should be understood that the positioning of the conductors applies equally to the arc lamp of Figs. 1 and 2.

The current to the positive holder is shown as introduced through'the insulated wire 46 which is supported to one side above the top of the holders; thence downwardly; thence parallel to the holders, the wire being shown as supported by the bar 12, thence upwardly andinto the positive holder. The wire to the negative electrode is shown at 47 and leads flrst to one side and over the holders, thence downwardly where it is secured to the bar 12 which connects conductor 47 to the negative electrode. The directions of the arrows show the directions. of the current passing through the wires and through the arc, the arrows 50 showing the direction of the current through the positive leading-in-wire; while the arrows 51 show the direction of current in the negative leading-in-wires.

In the above it will be seen that the plurality of conductors through which the current travels in the opposite direction to that through the arc are closely positioned and placed to that side of the are away from the exhaust opening; while the plurality of conductors through which the current passes in the same direction as that through the are are positioned adjacent but spaced to either side of said opening. By this means a very powerful deflecting influence is exerted on the arc, since, according to the wellknown laws of attraction and repulsion, the first mentioned conductors will repel the arc, while the second mentioned conductors will attract the arc. Furthermore, by positioning the conductors in the form of a triangle a remarkably steady flame is obtained which is of such steadiness as to be substantially undisturbed by air currents. Also by spacing the conductors which attract the flame so that the flame will pass between rather than toward either conductor, the damaging effect of the heat from the flame is avoided, the heat being lead directly up the chimney 3. In this form of arc, in order to secure the co-action of the negative flame with the positive flame as outlined in the aforementioned patent of Elmer A. Sperry, I find it preferable to position the negative electrode slightly nearer the repelling conductors as outlined above, so that a brushing contact across the mouth of the positive may be secured.

In employing an arc of this character, I flnd it unnecessary to employ a drum for enclosing the mechanism of the arc, since suflicient steadiness may be obtained by the methods outlined herein without shutting off all air currents. Furthermore, by burning the are more or less in the open the problem of removing the fumes is less serious, the weight of the light is greatly reduced, the front door rendered unnecessary, and the cost lessened very materially.

Such a lamp requires only a backing or shell 50' to support the reflector 39. If desired the shell may extend slightly beyond the reflector to aid in cutting ofl stray light from the crater 51 of the positive electrode although this function is mainly performed by said housing or hood 25. The said shell is pivoted on trunnions 52 in any suitable manner and supports the mirror 39. The electrode holders 4 and 6 are shown as supported from the shell by a tripod having two small legs 54, one of which is cut away, in Fig. 1, and a third hollow leg 3.

While I have described my invention in connection with high-intensity lamps it is to be understood that the principles thereof are applicable to ordinary arc lamps in which it is desired to steady the arc and direct the tailflame.

In accordance with the provisions of the patent statutes, I have herein described the principle of operation of my invention, together with the apparatus, which I now consider to represent the best embodiment thereof, but I desire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by other means. Also, while it is designed to use the various features and elements in the combination and relations described, some of these may be altered and others omitted without interfering with the more general results outlined, and the invention extends to such use.

Having herein described my invention what I claim and desire to secure by Letters Patent is: 1. In an open type searchlight, a shallow drum,

arc lamp mechanism positioned substantially beyond said drum and a plurality of supporting members for said mechanism fixed to said drum at spaced points, one of said members being hollow to permit drawing ofi the are vapors therethrough.

2. In a searchlight, a pair of electrodes arranged to produce an are, means for carrying oif vapors from the are positioned to one side of the arcing tips of said electrodes, a conductor for carrying current in the opposite direction to the normal current across the arc and positioned to repel the arc toward said means, and a plurality of spaced conductors for carrying current in the same direction as the arc and positioned to attract said are toward said means.

3. In a searchlight, a pair of electrodes arranged to produce an arc, means for carrying off vapors from the are positioned to one side of the arcing tips of said electrodes, a conductor arranged to one side of the arcing tips for carrying current in the opposite direction to the normal current across the arc and positioned to repel the arc toward said means, and a plurality of spaced conductors for carrying current in the same direction as the are, said last-named con ductors being positioned at the opposite side of said tips from said first conductor to attract said are toward said means.

4. An open type Searchlight comprising in combination with the reflector, a supporting shell, a pivotal mounting therefor, arc lamp mechanism for supporting the electrodes above the reflector,

a shield for the arcing tips of the electrodes, an exhaust flue connected therewith and means ineluding said flue for supporting said mechanism and shield from said shell.

5. In a high intensity flaming arc lamp, the combination with a pair of electrode holders, of supporting means for one of said holders, current conducting supporting means for the other or said holders located to one side of the position of the are, said holders being adapted to support the electrodes in substantially parallel positions, and a pair of spaced conductors on the side of the are opposite the first-named conductor whereby substantially similar burning conditions are produced as when the electrodes are positioned at an angle to one another.

6. In a searchlight, the combination with a pair of electrode holders, of a pair of electrical conductors adjacent one side and substantially parallel to said holders and spaced from each other, and a chimney disposed between said conduetors.

7. In a flaming arc searchlight, the combination with the electrode holders, of a pair of electrical conductors adjacent one side of said holders and spaced from each other, said conductors being adapted to carry a current in the same direction as the current across the are for attracting the flame of said arc, a chimney between said conductors having an opening to receive the gases produced by the arc, and means for creating a draft through said chimney away from the are.

8. In a searchlight, a pair of electrodes adapted to produce anarc, a conductor arranged to one side of the arcing tips of the electrodes adapted no to carry current flowing in the opposite direction to that flowing through the arc, and a plurality of spaced conductors adapted to carry current in the same direction as the current flows across the arc and positioned at opposite sides of said tips from 115 the first mentioned conductor and from each other, and a flue between said spaced conductors for carrying off the arc fumes.

PRESTON R. BASSE'I'T. 

